4

Hearing Technologies: Expanding Options

The hearing technology landscape is ever evolving and encompasses a wide range of products—from traditional hearing aids regulated as medical devices to consumer-technology products and hearing assistive technologies—with the overall goal of enabling the user to hear and communicate better in their homes (e.g., television), in public spaces (e.g., movies and lectures), and through phones or other communications products and systems. Both the access to and the affordability of these technologies are a concern in the United States and across the globe. Many people with hearing loss do not have hearing aids or other technologies. Of those who do have hearing aids, some choose not to use them. There are regulatory and policy challenges as well as research and design opportunities for improving hearing technologies so that they better meet the needs of individuals with hearing loss.

This chapter examines the broad range of hearing-related technologies. After a brief overview of the hearing technology landscape, including a discussion of the extent of use of these technologies and user satisfaction, the chapter examines studies on hearing aid efficacy and effectiveness (the nature and scope of the market is discussed in Chapter 5). The chapter then delves into the U.S. regulatory structure for hearing aids and other products that address hearing loss. The chapter closes with the committee’s recommendations on next steps for improving the accessibility and availability of hearing health care technology. Because the committee was charged to focus on nonsurgical interventions, the chapter does not address cochlear implants or implantable bone conduction hearing aids in detail.

OVERVIEW OF HEARING TECHNOLOGIES

The recently coined term hearables has been used to refer to a wide range of hearing- and ear-based technologies (Cannington, 2015; Hunn, 2015) that have been defined as “wearable technology for the ear” (Chandran, 2014; Hosford-Dunn, 2015). Hearable technologies include the devices and products relevant to hearing loss that are discussed in this report (see Box 4-1) as well as other products used via the ear, such as health-related technologies (e.g., monitors for heart rate and other health parameters) and the large variety of headphones, ear buds, and other music and streaming technologies. One estimate projects that the market for hearables will be more than $17 billion by 2020 (Hunn, 2015). Hearables can combine multiple functions and often feature innovations in style, color, and accessibility. The interest in audio technologies suggests a general public that has, and will increasingly have, personal familiarity with technologies that are for hearing or that are worn in the ear.

Hearing technology is undergoing rapid change as great advances in technologies and design features result in new products. Clayton Christensen used the term “disruptive innovation” to describe “a technology that brings a much more affordable product or service that is much simpler to use into a market. And so it allows a whole new population of consumers to afford to own and have the skill to use a product or service, whereas historically,

the ability to access was limited to people who have a lot of money or a lot of skill” (Smith, 2007, p. w288). Examples of disruptive innovations include personal computers, cell phones, and retail medical clinics, all of which are products or services that have increased consumer options, generally at lower cost. To disrupt an industry, an innovative technology needs to be coupled with business-model innovation to harness the full potential of the technology (Christensen et al., 2009). Outdated regulations and reimbursement models have the potential to entrench older technologies, even as more cost-effective and more accessible technologies become available. Thus, innovations in hearing technology create a potential for disruptive change in the market for hearing devices, products, and services, but whether the market transitions may depend on additional regulatory, business, and reimbursement factors. This complex topic has been the subject of recent recommendations by the President’s Council of Advisors on Science and Technology (PCAST) (Cassel et al., 2016; PCAST, 2015).

Hearing Aids

Hearing aids are medical devices defined by the Food and Drug Administration (FDA) as “any wearable instrument or device designed for, offered for the purpose of, or represented as aiding persons with or compensating for, impaired hearing.”¹ As detailed below, FDA regulates hearing aids as Class I or Class II medical devices. Hearing aids generally have a number of components including a microphone, analog-to-digital converter, digital sound processor, output transducer, and battery. Although often compared to glasses (termed “spectacles” in FDA regulatory language), current hearing aids cannot correct or restore normal hearing acuity to the extent that glasses or contact lenses can correct vision loss or restore normal visual acuity for many people. The general goal of well-fit hearing aids is to improve the audibility of even soft speech, music, and other sounds while assuring that these same sounds and other already audible sounds do not become uncomfortably loud. Hearing aids can be customized to meet the needs of the individual (see Chapter 3) including customization of the frequencies and intensities of sound and other adjustable parameters in the processing of algorithms.

Technological efforts to address hearing loss have a long history. Early hearing trumpets and other “hearing aids” focused on increasing the volume and directionality of sound. With a series of advances in technology (carbon transmitters in the late 1800s, vacuum tubes in the early 1900s, transistors beginning in the 1920s and in more common use in the 1950s, microprocessors in the 1970s and 1980s, and digitalization of sound in the

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¹ 21 C.F.R. 801.420.

1980s and 1990s), the size of hearing aids has decreased, while the capabilities to provide clearer sound have greatly improved (Mills, 2011; Mudry and Dodele, 2000; Washington University School of Medicine, 2016). In addition, advances in signal processing and other technologies, improvements in battery capabilities, and the advent of wireless access have made it possible for hearing aids to include telecoils (for coupling with compatible electronic products; see further description later in the chapter), directional microphones, noise reduction circuitry, direct audio input and processing algorithms that are intended to minimize background noise and maximize conversational sound, and capabilities for wireless signal reception for interactions with televisions, phones, computers and tablets, and other communication and hearing assistive technologies. The extent to which these components (and other innovations) are included in specific hearing aid products varies across the range of basic to premium level aids. Upgrades and variations include the extent and nature of Bluetooth capability, the inclusion of a telecoil, the number of channels, automatic switching among programs, feedback reduction, and smartphone applications to program or personalize the device (Consumer Reports, 2015; HLAA, 2016; Mamo et al., 2016; McCormack and Fortnum, 2013). Research and design efforts continue to focus on improvements in various capabilities.

The different types of air conduction hearing aids are distinguished primarily by the location where the device is placed—behind the ear, in the ear, or in the ear canal—with the various types providing varying levels of visibility, ease of control, and features (Consumer Reports, 2015; NIDCD, 2013). The literature on the effectiveness of hearing aids and an overview of the regulatory landscape is described later in this chapter.

For most adults with mild to moderate sensorineural hearing loss, a common complaint is difficulty in understanding speech, especially in noisy environments. When measured using a speech-in-noise task (see Chapters 3 and 6), the results may indicate that a more advantageous signal-to-noise ratio is required to understand speech than for individuals with normal hearing. In some cases, given that the hearing aid is well fit and improves speech audibility in higher frequencies, the signal-to-noise ratio may be improved. However, under certain conditions, even well-fit hearing aids may not necessarily improve the signal-to-noise ratio to result in improved speech recognition in noise. For these individuals with mild to moderate hearing loss, hearing assistive technologies and/or auditory rehabilitation may provide additional benefit.

FDA has established regulatory requirements for hearing aids that include technical standards, quality system regulation (including good manufacturing practice requirements), requirements for mandatory labeling and user instructional brochures, and requirements for a pre-purchase medical evaluation (or documented waiver) (see Chapter 3 and below for further

discussion of the medical waiver). These FDA regulations, along with a number of state regulations, have restricted the availability of hearing aids to being mainly dispensed through medical, audiology, or hearing instrument specialists. To date, FDA has not been receptive to proposals for over-the-counter (OTC) or direct-to-consumer hearing aids. This has led to the development of hearing-related technologies that are positioned as consumer electronics products rather than medical devices, including personal sound amplification products, or PSAPs (discussed below).

The immense demand for affordable and easy-to-deliver hearing health care in developing countries is resulting in innovations in the design of hearing aids and hearing assistive technologies aimed at increasing affordability and simplifying use. An estimated 360 million individuals in developing countries live with disabling hearing loss, and in 2004 the World Health Organization set out guidelines for hearing aids and services in an effort to support efforts to meet this demand (Olusanya et al., 2014; WHO, 2004). Although developing countries have a major need for low-cost hearing technologies, they often have a limited health care infrastructure with few audiologists and otolaryngologists. One avenue toward meeting the need would be the refinement of self-fitting hearing aids, which assess an individual’s hearing and transfer the resulting data directly to the hearing aid, which sets itself appropriately, ideally without computers or other external requirements (Caposecco et al., 2011; Convery et al., 2011; Wong, 2011). Other avenues being explored include varying hearing assistive technologies and the use of solar power and other innovative power options (McPherson, 2011; Parving and Christensen, 2004). These and other innovations in hearing aid technology and fittings may also increase the options for underserved populations in the United States (Clark and de Swanepoel, 2014).

Access to hearing health care services may also improve with greater availability of hearing aids that have an open platform approach to programming. For the purposes of this report, an “open platform” for hearing aid programming refers to a programming platform that allows any hearing health care professional to adjust the device settings to meet a consumer’s needs. “Open platform” does not refer to the proprietary software that confers general hearing aid functionality.

Currently, the settings on many hearing aids can only be adjusted by hearing health care professionals who have an agreement with a given manufacturer or distributor to sell that brand of hearing aid. Furthermore, many hearing health care professionals only sell one or a few different brands of hearing aids. A consumer who purchases a hearing aid from one hearing health care professional may find that the manufacturer or distributor has restricted access for adjusting the settings, and thus, the consumer may have to seek all additional programming services from the same distributor that originally sold him or her the product. In contrast, open platforms allow

the hearing aid to be programmed by any provider, increasing the portability of care and the number of professionals from whom the individual can obtain care. This approach allows consumers who want to switch to a different hearing health care professional, who are traveling, or who move to a new location to have their hearing health care needs addressed by the professional of their choice. Additionally, technologies will continue to evolve and may enable individuals to make hearing aid adjustments for themselves directly or through a mobile app or other pathway rather than having to depend on a professional every time an adjustment is needed.

The committee urges the development of the standards needed for an open platform approach and the collaborative efforts by manufacturers, distributors, and hearing health care professionals to ensure implementation. The committee also urges greater efforts on the part of those who sell hearing aids to educate consumers about whether a given hearing aid’s programming platform is open or closed. Additionally, consumer-friendly information on the programming parameters and other features of specific hearing aids should be furnished to consumers to allow easier comparisons between the devices (see also Chapter 6). These notifications should be provided prior to sale so that consumers can make informed purchasing decisions.

Extent of Hearing Aid Use

In the United States the prevalence of hearing aid use is significantly lower than the prevalence of hearing loss. In a report examining the results of the 1999–2006 National Health and Nutrition Examination Surveys (NHANES) (audiological testing was conducted from 1999 to 2004 in a sample of participants ages 50 to 69 years and in 2005 was conducted in all participants 70 years of age and older), it was estimated that hearing aids were worn by 3.8 million Americans, or 14.2 percent of those who had hearing loss (Chien and Lin, 2012) (see Table 4-1). An earlier report that was focused on NHANES participants ages 70 and older found a strong gradient of hearing aid use based on the severity of hearing loss, with 3 percent of those with a mild loss, 40 percent of those with a moderate loss, and 77 percent of those with a severe loss regularly wearing hearing aids (Lin et al., 2011). In a multivariable model, the severity of hearing loss, college education, and leisure noise exposure were positively associated with hearing aid use, but race/ethnicity, age, sex, and income were not significantly associated with the use of a hearing aid.

Bainbridge and Ramachandran analyzed NHANES data from 2005–2006 and 2009–2010 and found that among participants 70 years of age and older who were deemed to be hearing aid candidates (pure tone average [PTA] 0.5–2 kilohertz [kHz] > 35 decibel hearing level [dB HL] and who

TABLE 4-1
Prevalence and Number of Individuals 50 Years or Older with Hearing Loss^a Using Hearing Aids in the United States^b

^aHearing loss was defined as a speech-frequency pure tone average of hearing thresholds at 0.5-, 1-, 2-, and 4-kHz tones presented by air conduction in the better hearing ear of 25 dB or greater.

^bData were derived from the 1999–2006 National Health and Nutrition Examination Survey.

^cAll values represent percent prevalence unless otherwise noted.

^dNumbers do not sum to group total because of rounding.

NOTE: CI = confidence interval; dB = decibel; kHz = kilohertz.

SOURCE: Chien and Lin, 2012. Reproduced with permission. Copyright 2012. American Medical Association. All rights reserved.

reported moderate or worse hearing ability), just one-third used hearing aids (Bainbridge and Ramachandran, 2014). In this study, individuals with the highest incomes were more likely to use hearing aids than the poorest group, but these analyses did not adjust for education.

In the longitudinal Epidemiology of Hearing Loss Study, 14.6 percent of people with hearing loss were current hearing aid users, and 6 percent were former users (Popelka et al., 1998). Even among those participants who reported significant communication problems and handicap, only 33 percent reported currently using a hearing aid, while 32 percent of those with moderate to severe hearing loss reported current use. Factors associated with hearing aid use were older age, a greater severity of hearing loss, having a college education, poorer performance on word recognition tests, and self-reported hearing handicap and loss. Similar results of low hearing aid use were seen in a study of the adult children of participants in the Epidemiology of Hearing Loss Study, with only 4 percent of people with mild loss and 23 percent of participants with moderate-to-severe loss using hearing aids (Nash et al., 2013).

Although no race/ethnicity differences in hearing aid use have been seen in the NHANES data, this may be partly due to limited power, as the number of Hispanics/Latinos enrolled in the study was small. Data from the Hispanic Health and Nutrition Examination Survey showed that less than 10 percent of Hispanics/Latinos with hearing loss used hearing aids (Lee et al., 1991). Even among the participants with PTA > 40 dB HL, only 5 percent of men and 11 percent of women used hearing aids. A follow-up report from Lee and colleagues demonstrated that poorer Mexican Americans were nine times more likely to use hearing aids than other participants; the researchers speculated that the introduction of the Medicaid program may have contributed to the accessibility of hearing aids (Lee et al., 1996).

Hearing Aid User Satisfaction and Barriers to Use

To investigate the low use of hearing aids, studies have examined both the barriers to purchasing the devices and the barriers to use of the devices once purchased. The specific issues regarding cost as a barrier are discussed in Chapter 5.

As part of the longitudinal Epidemiology of Hearing Loss Study, Fischer and colleagues (2011) examined factors associated with acquiring hearing aids during 10 years of follow-up. Among participants with hearing loss in their better ear who were not using hearing aids, 36 percent started using them within 10 years. College graduates and people who reported greater hearing loss or judged their hearing as poor were more likely to become hearing aid users. When participants with hearing loss who had not acquired hearing aids were asked their reasons for not purchasing them, the

most frequent responses included “did not need it,” “cost,” “inconvenient to wear,” and “poor experience of others.”

A review of studies examining the nonuse of hearing aids that were already purchased found that the primary reasons given for nonuse were problems with obtaining improved speech clarity and sound quality and challenges with the fit, comfort, and maintenance of the device (McCormack and Fortnum, 2013) (see Box 4-2). MarkeTrak, an ongoing survey by the Better Hearing Institute, the educational arm of the Hearing Industries Association, has found high levels of satisfaction with hearing aids, particularly with more recent models that have newer technologies, but it also notes challenges (Abrams and Kihm, 2015). In a 2004 MarkeTrak survey, two-thirds of respondents who acknowledged that they had a hearing loss but said that they had not adopted the use of hearing aids reported that their barriers to hearing aid adoption included perceptions of or experiences with problems in hearing aid performance (e.g., whistling, background noise), disappointing results (e.g., hearing not restored), and poor reliability (e.g., due to short battery life or humidity) (Kochkin, 2007).

Knudsen and colleagues (2010) reviewed 39 studies on the correlates of help-seeking behavior, uptake of hearing aids, use of hearing aids, and satisfaction with the devices. The researchers found that those individuals who self-reported that they experienced hearing-related activity limitations or participation restrictions prior to hearing aid fitting had greater satisfaction and higher use. The extent of hearing loss (in the moderate range) was generally associated with seeking help and acquiring a device but was not always associated with increased use or satisfaction.

Ng and Loke (2015) reviewed 22 studies of older adults and noted a wide variety of audiologic determinants of hearing aid usage (largely self-reported), with the severity of hearing loss being a primary determinant, along with the type of hearing aid (greater use for those with more advanced signal processing features) and a greater tolerance for background noise. Nonaudiological determinants of the extent of hearing aid use included self-perception of a hearing problem, expectations of potential benefit, concerns of perceived stigma, and support from significant others or from group sessions.

One of the usability challenges for hearing aids that is reported particularly by older adults is that the small size of the devices can lead to difficulties with proper insertion, removal, and maintenance of hearing aids and changing their batteries. Limited vision and manual dexterity in older adults can exacerbate these problems (Clements, 2015; Erber, 2003). Furthermore, the hearing aids can be easy to misplace or lose.

The above studies indicate that sound quality, speech clarity, the amount of background noise, the ease and comfort of fit, battery reliability, and user expectations about the benefits and performance of hearing aids may be important factors affecting the use or nonuse of hearing aids. Although analogies have been drawn between hearing aids and eyeglasses, there are significant differences. Eyeglasses have corrective lenses and, when used, can generally correct visual acuity to the point that the user does not need any other assistive devices or strategies to see clearly. By contrast, hearing aids can improve the audibility of sound by amplification but are not able to restore normal hearing or fully improve communication abilities, especially in noise. Great strides have been made in hearing aids in the past 50 to 60 years, but issues regarding background noise and clarity of sound, among others, can limit benefits, particularly in certain situations and locations. Individuals who have hearing loss and use hearing aids can frequently benefit from hearing assistive technologies and from using strategies such as consideration of the location and proximity to (or away from) the source of the sound. Research efforts focused on hearing aid improvements continue to be needed, as are the development of performance standards for hearing aids and related products and the use of standardized terminology regarding device features to assist the consumer in directly comparing products and better understanding what can and cannot be expected from a given product (see also Chapter 6). Consistency across manufacturers in naming and describing the features of hearing aids and hearing assistive technologies will enable consumers to independently compare features and not rely solely on distributors and hearing health care professionals for that information.

Personal Sound Amplification Products

The term “PSAPs” refers to a wide range of consumer products that increase the level of sound sensed by the user. FDA guidance documents specify that to avoid classification as a medical device, PSAPs cannot be marketed in the United States as products intended for individuals with hearing loss or to compensate for hearing loss (FDA, 2009a,b, 2013b). A 2009 FDA guidance document defines a PSAP as a “wearable electronic product that is not intended to compensate for impaired hearing, but rather is intended for non-hearing impaired consumers to amplify sounds in the environment for a number of reasons, such as for recreational activities” (FDA, 2009b). FDA’s 2013 proposal for revised draft guidance offered some revisions and characterized PSAPs as products that

Some of these products have technical and performance characteristics quite similar to the hearing aids that FDA regulates. Determinations regarding whether a product is a “device” that FDA can regulate are based on the Federal Food, Drug, and Cosmetic Act (FDCA) definition of a device as “intended for use in the diagnosis of disease or other conditions, or in the cure, mitigation, treatment, or prevention of disease.”² FDA does not regulate PSAPs as medical devices, although FDA can regulate them under the electronic product provisions of the FDCA. As with other consumer products, the Consumer Product Safety Commission has the authority to examine any safety concerns about PSAPs.

Few data are available on the extent and nature of PSAP use. Additionally, the term PSAP is often used to describe a wide variety of products, so it can be hard to understand or compare consumer surveys. An analysis of a MarkeTrak survey reported that approximately 5 percent of respondents who did not own a hearing aid indicated that they owned a PSAP (Kochkin, 2010b). Those who owned a PSAP reported lower levels of self-categorized hearing loss (mild) and had an annual income averaging approximately $10,000 less than those who owned a hearing aid. When asked what they would do if PSAPs were not available, almost half of the PSAP owners indicated that they would not purchase custom hearing aids (Kochkin, 2010b).

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² Federal Food, Drug, and Cosmetic Act (FDCA), Public Law 75-717, 75th Cong. (1938) and amended. 21 U.S.C. § 321(h), 21 C.F.R. § 801.4.

A 2014 online survey by the Consumer Electronics Association (now the Consumer Technology Association [CTA]) found that of 1,551 U.S. adults who had been diagnosed with hearing loss or self-reported that they had trouble with hearing, approximately 30 percent owned a hearing aid, 11 percent owned a television amplifier, 11 percent owned an amplified telephone, and 6 percent owned another sound amplification product (CEA, 2014). Of those individuals who owned a PSAP, 51 percent said they used it to help listen to television, and 10 percent reported using the product every day.

The population-based Blue Mountains Hearing Study in Australia surveyed the use of what it termed “assistive listening devices” and found that out of 2,956 respondents, 4.4 percent reported using such a device in the past year, with the primary uses being to enhance use of the television or telephone (Hartley et al., 2010). Of current hearing aid owners in the study, 25.6 percent reported that they had used an assistive device in the past year.

Studies of the effectiveness of PSAPs and hearing assistive technologies have primarily been conducted using small samples of older adults and have noted a general lack of knowledge about hearing assistive technologies, although some studies with users familiar with the technologies have indicated user satisfaction in improving sound quality and speech understanding (e.g., Aberdeen and Fereiro, 2014; Southall et al., 2006). More research is needed to develop the data necessary for improved capabilities and to provide the information needed for comparisons between products and product features by consumers and professionals.

Hearing Assistive Technologies

Individuals with hearing loss, particularly those with moderate to severe hearing loss, may use a variety of hearing assistive technologies in addition to hearing aids to connect to or receive information from other communication avenues (such as the phone or television) or from sound systems in classrooms, theaters, places of worship, or other public spaces or for emergency alerts (see Box 4-3). Driven by the needs of consumers and the requirements of antidiscrimination laws such as the Americans with Disabilities Act (ADA),³ hearing assistive technologies span the range of products from those for personal and home use to systems available in public spaces and for larger audiences These services are often termed auxiliary aids and services in the ADA,⁴ which requires that

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³ Americans with Disabilities Act of 1990, Public Law 101-336, 101st Cong. (July 26, 1990).

⁴ Revisions to the ADA in 2010 included clarifying the scope of auxiliary aids and services to include providing a qualified note taker or interpreter, captioning (in multiple formats), assistive telecommunications products (e.g., telephone handset amplifiers, hearing aid–compatible telephones, text telephones, captioned telephones), videotext displays, and accessibility features in electronic documents (DOJ, 2014).

These types of products have also been termed “hearing assistance technologies.”

Improving the availability and effectiveness of hearing assistive technologies is a priority for achieving better hearing and communication for individuals with hearing loss. Improvements in these technologies and connections need to be accompanied by efforts to raise public awareness on the range of options available and to provide user-friendly instructions for connectivity and use. These efforts could be undertaken by hearing health care professional associations, hearing device manufacturers, and government entities such as the Federal Communications Commission (FCC) and the National Institutes of Health. Additionally, training for hearing

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⁵ 28 C.F.R. § 36.303.

health care professionals and for primary care providers and other health care professionals working with adults needs to emphasize the capabilities of hearing assistive technologies and best practices for instructing patients regarding their use and connectivity.

Hearing Induction Loop and Telecoil Technologies

Hearing induction loop technology allows the sound system in a room to connect wirelessly with an individual’s hearing aid via the telecoil in the hearing aid or via a neck loop receiver and ear phones, thereby eliminating the background noise and improving clarity of sound. These systems work through the installation of hearing loop wiring around the perimeter of the room that connects to the room’s sound system. The electromagnetic signals from the sound system are picked up by the telecoil in the hearing aid or cochlear implant or by the receiver.

Telecoils are available on most but not all types and models of hearing aids, but consumers do not always know that their hearing aid has this feature or that it can be added as an option⁶ (HLAA, 2016). Only 34 percent of 1,995 respondents to a 2008 MarkeTrak survey indicated that they were aware that their hearing aid had a telecoil (Kochkin, 2010a). Telecoils also enhance the performance of wired and wireless telephones.

In a survey of audio loop users, approximately 70 percent indicated that the loop significantly improved sound quality and speech intelligibility (Kochkin, 2014). Respondents also noted that hearing induction looping empowers consumers because they can walk into a venue with an induction loop and turn on the telecoil sensor without the need to ask for assistance or ask for another piece of equipment (receiver); by being unobtrusive to use, the technology maintains a user’s privacy. Furthermore, performance standards for induction loop technology provide the consumer with a technology that can be used across venues and manufacturers, whereas many other hearing technologies are proprietary. Some states have recognized the value of the telecoil to couple with an induction loop by mandating that consumers be informed about the telecoil when they purchase their hearing aids. Hearing induction loops have been installed in some public spaces, such as movie theaters, places of worship, and other large venues, but they can also be installed in private homes (Shaw, 2012) and vehicles (HearingLoop.org, 2015). Efforts are under way in some communities to expand the use of this technology (see Chapter 6).

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⁶ The Consumer’s Guide to Hearing Aids notes that the majority of hearing aids have telecoils as a standard feature or as a feature that is available to be added (HLAA, 2016).

FM and Infrared Technologies

FM (frequency-modulated) systems use radio signals to transmit sound directly from the speaker’s microphone or other sound system. Some types of hearing aids can process the wireless FM transmissions. In other cases, a body-worn receiver is used that is connected to earphones or a neckloop is used that converts the transmission to an electromagnetic signal that can be picked up by the telecoil in the hearing aid (ASHA, 2016; Chisolm et al., 2007b; Kim and Kim, 2014). These systems are often used in classrooms and places of worship and can be used to transmit sound from radio, television, and other sources. Radio signals are able to penetrate walls, and mixed signals can result unless different frequencies are used. Studies on the effectiveness of FM systems in improving speech perception have primarily examined the use of this technology by children in classroom settings (e.g., Bertachini et al., 2015; Hawkins, 1984; Hawkins and Schum, 1985).

Infrared systems use infrared light waves to transmit to a personal receiver. As with the FM systems, the infrared system uses a receiver and headphones or a neckloop and hearing aid telecoil. The infrared systems have the advantage of containing the signal in the room (and thereby having less interference from other competing signals), but they have the disadvantage of potentially competing with natural light (Holmes et al., 2000; Kim and Kim, 2014).

Captioning

Captioning involves the transcription of discussions or programming into text on a screen and can be done on-site or remotely. Captioning is often done in real time for live events such as sports events or conferences, and it can be projected through television and other media, through a website, or directly onto a screen visible in the location of the event. Beginning in 1993, the ADA required all televisions 13 inches or larger to have closed captioning capabilities with text for the auditory portion of programs (Holmes et al., 2000). Captioned telephones are also available and can be used in conjunction with the Telecommunications Relay Service (see next section).

Interconnectivity—Wireless and Other Information and Communication Technologies

Individuals with hearing loss often face challenges involving the interoperability and compatibility of information and communications technologies (e.g., phones, television, or wireless networks) with hearing aids and other products. Beginning in the 1980s and 1990s a number of laws

were passed in the United States that focused on ensuring that telephone and television and other electronic communications would be accessible to individuals with hearing loss and other Americans with disabilities (see Box 4-4).

Efforts by the U.S. Access Board (responsible for issuing standards and guidance relevant to the ADA) and other organizations and agencies include a focus on the issues of compatibility and interoperability between and among wireless communications products and systems and hearing technologies, including revised and common wireless standards (Access Board, 2015).

Mobile apps and smartphones have the potential to offer a variety of options for individuals with hearing loss (Mamo et al., 2016; Paglialonga et al., 2015). Smartphones can be used via Bluetooth to initially set up a

hearing aid or to personalize and program the device (Mamo et al., 2016). One analysis of mobile health applications for eight health conditions noted the paucity of mobile applications for hearing loss (Martinez-Perez et al., 2013). The apps related to hearing were primarily for the purpose of hearing checks or providing educational tools. Screening for hearing loss is also a potential use (Peer and Fagan, 2015) (see below for information on FDA guidance documents regarding mobile apps; see also Chapter 3).

Phones are required to meet American National Standards Institute (ANSI) standards specifying the level of volume and other sound parameters that must be attainable. The FCC requires that wireless phones meet the ANSI C63.19 standard regarding compatibility with hearing aids. Additionally, telephones are available that provide greater amplification, and other assistive technologies can also be used in conjunction with phone

calls. The FCC’s Telecommunications Relay Service offers a variety of options to assist individuals who have hearing loss with placing and receiving phone calls (see Box 4-5). A recent FCC report to Congress highlighted several consumer-related issues including ensuring seamless connections between smartphones and hearing aids and providing more extensive consumer information online and in retail settings to help customers compare features of phones and other technologies (FCC, 2014). Recent FCC proposed rule making focuses on compatibility issues (FCC, 2015b).

Among the other technologies that offer potential for helping individuals with hearing loss is the expanded use of high-definition voice (also referred to as wide-band audio), which broadens the range of frequencies transmitted and the number of audio samples per call to allow less background noise and provide more easily distinguishable sounds (Chang, 2013).

A 2015 survey by the Rehabilitation Engineering Research Center on Telecommunications Access at Gallaudet University found that among 420 respondents with hearing loss (the majority self-reporting that they had severe or profound hearing loss) who regularly used telephones, the major needs reported for improved phone use were

• Better telephone sound quality;
• Improved telephone captions, which are more accurate, have shorter delays, or both;
• Better ways to test telephone products to find which work for a given individual;
• More affordable prices for accessories and other special telephone equipment;
• More or better information about telephone communication options for people with hearing loss;
• Better options for listening to voice mail;
• More or better information about hearing aid compatibility for cell phones;
• The ability to hear over the telephone using both of an individual’s hearing devices at the same time;
• More training on strategies an individual can use to improve his or her telephone communication with people who are difficult to understand; and
• More attention to assessing an individual’s telephone communication needs by the individual’s audiologist or hearing instrument specialist.⁷

Emergency Communications

Ensuring accessibility of the nation’s emergency communications systems requires that the systems have specific features for those with hearing loss. These systems have three key components: (1) 911 call processing and delivery through public safety answering points and call dispatch; (2) the Emergency Alert System (national and regional); and (3) radio and television station transmission of news and updates regarding emergency information, which are mandated to be provided both aurally and in a visual format (such as closed captioning or other methods) (FCC, 2015a). The FCC requires that 911 landline and wireless services be compatible with text telephone devices. Additionally, efforts are ongoing to update and expand the methods of emergency communications to include text-to-911 capabilities for individuals with hearing loss or other disabilities (FCC, 2015c). An increasing number of public safety answering points (local centers where 911 calls are processed) have the capability to receive text-

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⁷ Personal communication, Voice Telecommunications Access Survey, from Linda Kozma-Spytek, Senior Research Audiologist, Technology Access Program, Gallaudet University. Received February 19, 2016. Available by request from the National Academies of Sciences, Engineering, and Medicine Public Access Records Office. For more information, email PARO@nas.edu.

to-911 (FCC, 2016). Weather emergency information can be provided to those who have hearing loss through connections to the National Oceanic and Atmospheric Administration Weather Radio system which can include providing text displays, alerting lights, or other mechanisms (NOAA, 2015). Smoke and carbon monoxide detectors are available with strobe lights, as are emergency devices that use vibrations to alert the user to emergency situations.

EFFECTIVENESS OF HEARING AIDS AND OTHER ASSISTIVE PRODUCTS

Recent research on the effectiveness of hearing aid use (and the use of other technologies, such as cochlear implants) has largely focused on the impact of that use on speech development and learning in children with hearing loss. Fewer peer-reviewed studies have examined the efficacy (performance under controlled conditions, usually in a clinical trial) and effectiveness (performance in real-world settings) of hearing aid use by adults, particularly comparing various types of hearing aids or comparing hearing aids with PSAPs or hearing assistive technologies. As noted in a 2001 review by Maki-Torkko and colleagues, “only a few studies on HA [hearing aid] outcomes meet strict scientific criteria and even fewer studies correlate rehabilitation outcome with the degree of HI [hearing impairment], disability or handicap” (Maki-Torkko et al., 2001, p. 8). As discussed above, studies have looked at the usage of hearing aids and owner’s satisfaction and barriers to use. However, the outcome measures used to assess the efficacy and effectiveness of hearing aids (e.g., measures of speech recognition) vary widely, and a consensus is needed on standard outcome measures.

Studies of Efficacy and Effectiveness of Hearing Aids

Studies of the effectiveness of hearing aids have been primarily experimental studies that have examined the impact of specific technical aspects or components of the hearing aid device using small numbers of study participants, and many of these studies have been focused on technical rather than clinical or functional outcomes (Humes and Krull, 2012). These studies, which often compare different versions of a technology, have investigated such features as directional and omnidirectional microphones (e.g., Gnewikow et al., 2009; Hawkins and Yacullo, 1984; Keidser et al., 2013; Wu et al., 2013), multimemory and volume controls (e.g., Banerjee, 2011), noise reduction technologies (e.g., Oeding and Valente, 2013), and various types of circuits and compression options (e.g., Hawkins and Naidoo, 1993; Kokx-Ryan et al., 2015; Moore et al., 2001; Shanks et al., 2002). During the transition from analog to digital hearing aids over the past

20 years, studies examining the technologies had varying results, due in part to variation in the outcomes assessed. Johnson and colleagues (2016) reviewed 10 studies of hearing aid use by adults with mild hearing loss and found positive benefits of amplification using a variety of measures. Taylor and colleagues (2001) reviewed one randomized controlled trial and seven randomized crossover trials and found no significant differences in user function and quality of life assessments between analog and digital devices when pooling the data.

Assessing the impact of hearing aids on quality of life is a challenge because of the multiple comorbidities in many participants and the gradual onset of hearing loss in many adults. A meta-analysis of studies examining the impact of hearing aids on quality of life found no effect when using general health-related quality of life measures but a medium to large effect when using hearing-specific questionnaires; however, the meta-analysis included only one randomized controlled trial (Chisolm et al., 2007a).

Only a few studies have used control groups or randomized methodologies. As noted by Van Vliet, “Peer-reviewed publications describing performance of various techniques and hearing aid circuits are available, but high-quality evidence about what works for patients in the form of randomized, blinded studies designed to answer critical questions about candidacy for hearing aids, hearing aid selection, fitting, and rehabilitation are very rare” (Van Vliet, 2005, p. 416). A clinical trial conducted by the Department of Veterans Affairs (VA) and the National Institute on Deafness and Other Communication Disorders (NIDCD) examined hearing aid benefits among 360 participants with sensorineural hearing loss (Larson et al., 2000; Noffsinger et al., 2002; Shanks et al., 2002). The participants were randomized in order to examine the results of using three different hearing aid circuits. At the time the study was conducted, these three circuits made up 70 percent of the U.S. hearing aid market. Each circuit was used for 3 months, six sequences of circuits were used, and the study was double blinded. The major outcomes examined were loudness, noise interference, and overall quality, and the outcome measures involved speech recognition tests, ratings of perceived sound quality, and self-assessed subjective assessments of benefit. When compared with unaided listening, the participants reported substantial benefit with hearing aids using all three circuits. Small differences were noted between the circuits on ratings of loudness and on the distortion of sounds.

A study by Yueh and colleagues (2001) randomly assigned 30 veterans with service-connected hearing loss (and eligible to receive a hearing aid through their veteran benefits) to receive either a programmable hearing aid with a directional microphone or a nonprogrammable aid. Hearing-related quality-of-life measures were compared among those two groups and also with 30 veterans with non-service-connected hearing loss who

either did not have a hearing aid or who received a hearing assistive technology product. The greatest improvements in hearing-related quality of life were noted by those using the programmable hearing aids, followed by those who received the nonprogrammable aid and then the hearing assistive product, and the lowest scores were for those with no hearing technologies. Similarly, Humes and colleagues (2009) randomly assigned groups of older adults with hearing loss to four types of hearing aids (varying by single-versus multichannel technology and omnidirectional versus bidirectional microphones) and found improvements in speech recognition in all groups with little difference seen between the technologies.

A more recent study conducted by Cox and colleagues (2014) examined the results of laboratory tests and journal entries of speech understanding for 25 participants with bilateral mild to moderate sensorineural hearing loss who used four types of hearing aids (two basic and two premium level) in a randomized crossover trial. The hearing aid fittings were conducted following a best-practice five-step approach that included programming of the hearing aids using the manufacturer’s proprietary algorithm and matching real-ear performance to national prescription goals. Participants ranged from new to experienced hearing aid users (mean age of 70.4 years). Each type of hearing aid was used for 1 month, with participants engaged at the end of each month in laboratory speech understanding tests and responding to a set of standardized questionnaires; the participants also recorded journal entries of their experiences with the hearing aids throughout the month. The study found benefits associated with all four types of hearing aids, with experienced users noting greater benefits than new users. No statistically significant differences were found in speech understanding between those using the premium and the basic hearing aids. The researchers also conducted a single-blinded, repeated, crossover trial in which 45 participants used hearing aids with premium and basic features (participants were blinded to the features) and responded to a variety of quality-of-life and hearing assessments and interviews (Cox et al., 2016). On average, the participants did not note any significant differences between the hearing aids with premium features and those with basic features when assessing their use in daily life. These studies are at the forefront of efforts to provide independent comparative data on the effectiveness of hearing technologies. Additional studies are needed that use larger sample sizes across age ranges and control for prior experience with hearing aids to examine hearing characteristics and use of the broad range of products and devices in laboratory and real-world hearing environments.

Studies of the use of hearing aids have found no clear evidence that hearing aid users become acclimatized to hearing aids or have positive changes in hearing performance over time (Humes and Wilson, 2003; Humes et al., 2002; Turner et al., 1996). While it might be expected that

hearing aid users would become more familiar with amplification and would note improvements in understanding amplified speech, the results of studies examining this expectation have not been consistent; however, the numbers of individuals studied has been limited. Further efforts and innovative approaches to understanding and optimizing the benefit of sustained use of hearing aids are needed.

Comparisons of Hearing Aids and Other Products

The evidence base of comparative studies among various types of devices and products is also scant. Studies that have included “non-hearing aid products” have described them in varying ways, making it difficult to distinguish a study examining what in the United States would be considered a PSAP from hearing assistive technologies or from low-cost hearing aids (which in some countries are sold as OTC).

Callaway and Punch (2008) examined the electroacoustic characteristics of 11 types of “OTC hearing aids,” although it was not clear which were marketed as hearing aids and sold through mail order or the Internet and which were PSAPs. Eight of the products (termed “low-range” by the authors) were sold for less than $100 and three were in the mid-range group ($100 to $500). The study conducted analyses of gain and output for three hearing loss patterns and found that the low-range products primarily worked for hearing loss at low frequencies and were “electroacoustically inadequate to meet the needs of the hearing impaired” (p. 14), while the mid-range products could meet most or all of the National Acoustic Laboratories parameters. In 2000, Cheng and McPherson reported on a comparison conducted in Hong Kong of 10 OTC hearing aids costing less than $250 each (U.S.). Hearing aids can be purchased OTC in Hong Kong, and some of the products sold there may be more similar to PSAPs or to basic hearing aids. The study found that most of these products performed within the ANSI standards for hearing aids, with several being outside of the equivalent input noise and total harmonic distortion levels, and that most were more appropriate for helping people with low-frequency hearing loss than the high-frequency loss often experienced by older adults (Cheng and McPherson, 2000). An update of this study examined 10 OTC products and found similar results, with little change in electroacoustic characteristics or performance in the intervening decade (Chan and McPherson, 2015).

A study examining the acoustic performance of several more recent direct-to-consumer amplifying products (the authors describe these products as a “newer generation of hearing devices that comprise a higher price point [i.e., cost $200–$400]” found variations in parameters including frequency-specific gain, signal-to-noise ratio, and listening comfort

and found that a number met the targeted performance levels (Mamo et al., 2016).

Research Needs

Research on hearing technologies is funded and conducted largely by the private-sector companies that produce hearing aids and hearing assistive technologies. It is estimated that the private sector annually invests $600 million in research and development aimed at improving hearing aids and developing new features, products, and systems (HIA, 2015).

Federal agencies with a focus on research on adult hearing loss include NIDCD, the National Institute on Aging, the VA, and the Department of Defense (e.g., DoD Hearing Center of Excellence, 2016; NIDCD, 2015; VA, 2015). Another avenue for funding university-based research on devices and technologies relevant to hearing loss is through the Rehabilitation Engineering Research Centers (RERCs) (ACL, 2015). These centers are charged with conducting studies of technology, systems, and devices across the range of disabilities. Relevant centers working on hearing include the RERCs on hearing enhancement, on universal telecommunications access, and on wireless technologies (Galludet University, 2013; University of Wisconsin–Madison and Galludet University, 2016; Wireless RERC, 2016). RERCs are supported by the National Institute on Disability, Independent Living, and Rehabilitation Research (formerly the National Institute on Disability and Rehabilitation Research) now located in the Department of Health and Human Services.

Efforts are needed across the academic, private, government, and nonprofit sectors to provide the research, outcome measures, and standards needed to improve hearing health care. Research and standards needs identified by the committee relevant to this chapter include

• Effectiveness and comparative-effectiveness studies of hearing technologies using consumer-relevant parameters across the varying levels of severity of hearing loss;
• Continued innovative research and design of hearing aids and hearing assistive technologies with a focus on improving hearing clarity, facilitating ease of use (particularly for older adults), and compatibility with the other assistive and communications technologies;
• The development of minimum performance standards for examining the effectiveness of hearing devices in real-world situations;
• Consensus criteria for defining an individual with hearing loss as a candidate for a hearing aid or other hearing device; and
• Product labeling comprehension studies.

REGULATORY STRUCTURE AND STANDARDS

Hearing aids, hearing aid compatibility, and to some extent PSAPs are subject to federal regulation in the United States by FDA, the FCC, and Federal Trade Commission (FTC). Hearing aids are also subject to regulation under state regulatory laws, including licensing laws. This section provides an overview of these regulatory laws and describes their impacts on accessibility to hearing health care for adults.

Food and Drug Administration

FDA regulates hearing aids as medical devices under the FDCA. A “device” is defined in the statute as an article or instrument intended for use in the diagnosis of disease or other conditions; intended for use in the cure, mitigation, treatment, or prevention of disease; or intended to affect a structure or any function of the body.⁸

Overview of FDA Regulation of Medical Devices

Under the FDCA, medical devices are regulated under a risk-based framework with three classes of devices:

• Class I devices are considered the lowest risk and are subject to general controls, but they are not required to undergo premarket review by FDA (with some limited exceptions). Although usually exempt from 510(k) requirements, a new device in Class I can lose that 510(k) exemption if it has a different intended use or a “different fundamental technology” than the other devices in that product classification.⁹ Examples of Class I medical devices include dental floss, medical gloves, and tongue depressors.
• Class II devices are moderate risk and are subject to general controls, special controls, and premarket review by FDA (with some exceptions where the device is exempted from premarket review). Examples of Class II medical devices include powered wheelchairs and some pregnancy test kits.
• Class III devices are the highest risk, such as implantable devices or life-supporting or life-sustaining devices. Class III devices are subject to general controls and also require premarket approval by FDA prior to marketing. Examples of Class III medical devices

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⁸ FDCA § 201(h), 21 U.S.C. § 321(h).

⁹ See, e.g., 21 C.F.R. § 874.9 (limitations on exemption).

“General controls” include the registration of the manufacturer’s device establishment, listing of the devices in commerce, quality system regulations including design controls and specific requirements for good manufacturing practices (unless exempted), adverse event reporting, labeling, and other requirements.¹⁰ Design controls apply to Class II and Class III devices but not to Class I devices unless the devices are automated with computer software (or otherwise specified in the regulation).¹¹ “Special controls” include guidance documents, guidelines, performance standards, post-market surveillance, and other controls to provide reasonable assurance of the safety and effectiveness of the Class II device.¹² FDA has three premarket pathways (see Box 4-6).

FDA regulates the labels and labeling of all devices under its jurisdiction. Labeling is information that “accompanies” the device, which can be more than just physical accompaniment. The statute requires that labels and labeling be truthful, accurate, and not misleading. The labeling of a medical device must include adequate directions for use and adequate warnings to protect users.

When FDA authorizes a device for marketing, the device can be limited to use by or on the order of a physician or other health professional (prescription use) or authorized for OTC purchase and use by consumers (OTC use).

FDA also has the authority to impose restrictions on the sale, distribution, or use of a device—making it a “restricted device.” Such restrictions can be imposed as a condition of approval in a premarket approval (PMA) order¹³ or by promulgating a regulation for devices that undergo 510(k) review or that are exempt from 510(k) review.¹⁴ FDA is authorized to regulate the advertising of restricted medical devices.¹⁵

Current FDA Regulation of Hearing Aids as Medical Devices

FDA has classified hearing aids under several different classification regulations, based on the intended use and risk of the different technologies. As defined in FDA regulations, a hearing aid is a “wearable sound-

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¹⁰ FDCA § 513(a)(1)(A), 21 U.S.C. § 360c(a)(1)(A).

¹¹ 21 C.F.R. § 820.30(a).

¹² FDCA § 513(a)(1)(B), 21 U.S.C. § 360c(a)(1)(B).

¹³ FDCA § 515(d)(1)(B)(ii), 21 U.S.C. § 360e(d)(1)(B)(ii).

¹⁴ FDCA § 520(e), 21 U.S.C. § 360j(e) and FDCA § 502(q)&(r), 21 U.S.C. § 352(q)&(r).

¹⁵ FDCA § 502(q)&(r), 21 U.S.C. § 352(q)&(r). The Federal Trade Commission otherwise regulates the advertising of medical devices.

amplifying device that is intended to compensate for impaired hearing.”¹⁶ Air conduction hearing aids amplify and deliver sounds to the external ear canal via air conduction. Bone conduction hearing aids involve an implant that is placed behind the ear, and amplified and processed sound is conducted via the skull bone to the cochlea. An air-conduction hearing aid is a Class I device that is exempt from premarket review but which remains subject to quality system regulation (including good manufacturing practices) and other FDA requirements. As with other Class I devices, a specific

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¹⁶ 21 C.F.R. § 874.3300.

air-conduction hearing aid can lose its 510(k) exemption if it has a different “intended use” or a “different fundamental technology” than other devices in that product classification.¹⁷ A bone-conduction hearing aid is a Class II device, subject to 510(k) notification requirements. FDA has recognized consensus standards that are applicable to both of these classes of hearing aids, including ANSI/Acoustical Society of America (ASA) standards (FDA, 2013a).

FDA has classified wireless air-conduction hearing aids as Class II with special controls.¹⁸ The applicable special controls are testing to validate electromagnetic compatibility; design and performance data to validate wireless technology functions; and labeling that specifies “appropriate instructions, warnings, and information relating to [electromagnetic compatibility] and wireless technology and human exposure to non-ionizing radiation.” Wireless air-conduction hearing aids are exempt from 510(k) notification requirements.

A transcutaneous air conduction hearing aid system is a “wearable sound-amplifying device intended to compensate for hearing loss without occluding the ear canal.”¹⁹ The system involves of an air-conduction hearing aid attached to tube system that is surgically fitted between the back of the outer ear and outer ear canal. It is Class II, requires a 510(k) notification, and is subject to the special controls specified in an FDA guidance document for this device type (FDA, 2002).

FDA also regulates as devices various testing equipment and accessories. For example, a “hearing aid calibrator and analysis system” is a Class II device, defined as an “electronic reference device intended to calibrate and assess the electroacoustic frequency and sound intensity characteristics emanating from a hearing aid.”²⁰

Cochlear implants and other implantable hearing devices are in Class III and require FDA granting of a PMA prior to marketing. These devices require surgery for implantation and are therefore not part of the charge to the committee and the discussion in this report.

In 1977, FDA issued regulations that made hearing aids “restricted devices” subject to various restrictions on sale, distribution, and use specified in the regulations.²¹ These regulations define “hearing aid” as “any wearable instrument or device designed for, offered for the purpose of, or represented as aiding persons with or compensating for, impaired hearing.”²² These regulations also set forth labeling requirements for hearing aids,

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¹⁷ 21 C.F.R. § 874.9.

¹⁸ 21 C.F.R. § 874.3305.

¹⁹ 21 C.F.R. § 874.3950.

²⁰ 21 C.F.R. § 874.3310.

²¹ 21 C.F.R. §§ 801.420 & 801.421.

²² 21 C.F.R. § 801.420(a).

including the requirement for a user instructional brochure, which must be provided to the prospective user by the dispenser of the hearing aid. The brochure must include a “Warning to Hearing Aid Dispensers” that informs dispensers that they should advise prospective users to consult a physician whenever they find the prospective user to have certain medical conditions. The user instructional brochure must also include an “Important Notice for Prospective Hearing Aid Users” that users should have a medical evaluation by a licensed physician before purchasing a hearing aid (see discussion in Chapter 3). That notice also includes the following statement:

A hearing aid dispenser cannot sell a hearing aid unless the prospective user provides a written statement signed by a licensed physician stating that the hearing loss has been evaluated and the person is a candidate for a hearing aid or, alternatively, the prospective user signs and presents a waiver of the medical evaluation. The prospective user must be given the opportunity to review the user instructional brochure for the hearing aid prior to signing the waiver of medical examination (see Chapter 3).

FDA has permitted the marketing of disposable hearing aids.²³ In addition, FDA has not objected to Internet sales of Class I hearing aids where a mechanism is provided to ensure compliance with the regulations (e.g., FDA, 2005). Often the purchaser is asked to electronically read the waiver form and is given the option to accept the terms of the waiver online.

Over the years, hearing technology companies have petitioned FDA to amend its regulations to eliminate the medical evaluation requirement and to allow the OTC sale of hearing aids (e.g., Etymotic Research, 2003; GudHear, 2003). FDA has denied those petitions. One petitioner argued that OTC hearing aid safety could be ensured by restricting peak OSPL-90 (output sound pressure level with 90 dB SPL input) to 115 dB SPL (sound pressure level) or less in order to prevent hearing damage or tinnitus and by requiring that eartips pass standard tests for allergic reactions and real-world testing for ear canal safety (Etymotic Research, 2003, p. 3). Another petitioner stated that labeling could provide adequate information to educate potential users about hearing loss and when to consult a hearing health care professional. As an example, the petitioner recommended providing

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²³ E.g., FDA-cleared 510(k) notifications K081136 and K021867.

the following information to a prospective hearing aid purchaser in person, by website, or otherwise (GudHear, 2003, p. 4):

• A hearing aid will not restore normal hearing and will not prevent progressive hearing loss, and will not improve the underlying causes of organic hearing loss.
• Some hearing loss is caused by conditions that can be medically corrected. The following signs indicate the need for a medical evaluation by a licensed physician, preferably a physician who specializes in diseases of the ear:

1. Congenital or traumatic deformity of the ear
2. Pain or discomfort in the ear
3. History of active drainage from the ear within the past 90 days
4. History of sudden or rapidly progressing hearing loss
5. Unilateral hearing loss or a difference in hearing between ears in the past 90 days
6. Excessive earwax
7. Foreign body in the ear canal
8. Acute or chronic dizziness

The medical conditions identified above correspond to the “red flag” medical conditions that must be identified in the warning statement to hearing aid dispensers in the user instructional brochure required by 21 C.F.R. § 801.420(c)(2) (for more discussion of the “red flag” medical conditions, see Chapter 3).

FDA denied the petitions requesting an OTC hearing aid classification, citing concerns that a medical evaluation is necessary to ensure that the “red flag” ear conditions would not be “undiagnosed and unevaluated” and to avoid delays in diagnosis and management of medically treatable conditions that cause hearing loss (FDA, 2004a,b).

Current FDA Regulation of PSAPs as Nondevice Articles or Instruments

As noted above, FDA’s regulations define a “hearing aid” as any wearable instrument that is designed, offered, or represented “as aiding persons with or compensating for impaired hearing.” This definition flows from the statutory definition of a medical “device” as intended for use in the cure, mitigation, or treatment of a disease, or intended to affect a structure or function of the body.

Given the technological advances since FDA promulgated the hearing aid regulations in 1977, the interest of consumers in taking more control over their own health and wellness, and FDA’s refusal to create an OTC

hearing aid category, some manufacturers have been interested in selling products that enhance hearing without complying with the restrictions on sale, distribution, and use imposed under FDA’s hearing aid regulations. As a result, some manufacturers began to market hearing aid devices directly to consumers, sometimes by seeking to comply with the federal restrictions in 21 C.F.R. §§ 801.420 and 801.421 and sometimes not. Some manufacturers sought to market technologies with labeling and advertising claims that the products could help people to hear better, but without calling the products “hearing aids” (FDA, 2009a).

FDA eventually issued a guidance document to address this new category of products that FDA called personal sound amplification products, or PSAPs. As one manufacturer explained, “It is important to realize that the only reason most PSAP manufacturers—including the Petitioner’s company—developed PSAPs was to provide a low-cost alternative to hearing aids for those who could not afford hearing aids or did not want to be burdened by FDA regulatory requirements” (Etymotic Research, 2014, p. 15).

FDA issued a guidance document in 2009 to recognize the category of nondevice products called PSAPs that would be distinguished from the medical device “hearing aid” (FDA, 2009b). As defined in that guidance document, a PSAP would be “intended to amplify environmental sound for non-hearing impaired consumers. They are not intended to compensate for hearing impairment.” PSAPs would be permitted for uses including “listening to lectures with a distant speaker, and listening to soft sounds that would be difficult for normal hearing individuals to hear (e.g., distant conversations, performances).” That guidance document stated that PSAPs would not be medical “devices” because they were not intended to cure, mitigate, or treat a disease and did not alter the structure or function of the body and thus were not within the statutory definition of “device” in the FDCA.

In 2013, FDA issued a draft guidance document for comment that was intended to supersede the 2009 PSAP guidance document (FDA, 2013b). This draft guidance document retains the same description of uses that would be considered appropriate for a PSAP, but it also includes lists of uses that FDA considers “listening situations that are typically associated with and indicative of hearing loss” and thus within the “hearing aid” device classification. FDA’s 2013 draft guidance states:

The 2013 draft guidance document has been viewed as more limiting than the 2009 guidance document, in that statements such as that above appear to be further restricting the types of products, claimed uses, and performance claims that would be appropriate for the PSAP product category. Nevertheless, FDA clearly stated in both the 2009 and 2013 documents that the agency’s view was that PSAPs were not intended to be used by individuals with hearing loss.

As nondevice products, PSAPs would not be subject to FDA regulatory controls applicable to medical devices. Thus, there would be no FDA control of the design, manufacturing, or labeling of PSAPs (other than to ensure the labeling did not cause the product to be a hearing aid). Nor would PSAPs be subject to the product performance standards that FDA has recognized as applicable to hearing aids (e.g., ANSI voluntary standards recognized by FDA as applicable to hearing aids).²⁴ Moreover, the FDA regulations imposing the restrictions on sale, distribution, and use—including requirements pertaining to medical evaluations, hearing aid dispensing, and the user instructional brochure—would not apply to PSAPs.

FDA did advise, in both the 2009 guidance and the 2013 draft guidance documents, that PSAPs are electronic products that emit sonic vibrations and thus are subject to the electronic product provisions of the FDCA that apply to both nondevice products and medical devices.²⁵ Manufacturers of PSAPs are required to report defects (including product failure to perform to design specifications and causing certain types of injury)²⁶ and adverse events relating to injurious or potentially injurious exposure of a person to electronic product radiation (including sonic, infrasonic, or ultrasonic waves).²⁷ PSAP manufacturers are also subject to requirements for repurchase, repair, or replacement of products that have a defect or that fail to comply with an applicable federal standard.²⁸ These regulations for electronic products are far more limited than the medical device regulatory requirements.

At the time it was issued, FDA established a regulatory docket for the public to submit comments on the 2013 PSAP draft guidance. In January 2016, in response to a PCAST report recommending OTC hearing aids

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²⁴ As noted elsewhere, the Consumer Technology Association has undertaken a project to draft voluntary standards that would apply to PSAPs.

²⁵ FDCA §§ 531-542, 21 U.S.C. §§ 360hh-360ss; 21 C.F.R. § 1000.15(d).

²⁶ 21 C.F.R. Part 1003.

²⁷ 21 C.F.R. §§ 1000.3 & 1002.20.

²⁸ 21 C.F.R. Part 1004.

(PCAST, 2015) and this ongoing Academies study, the agency reopened the comment period on the draft guidance (FDA, 2016a). FDA asked the public to address the following issues:

1. The degree to which current FDA requirements are a barrier to hearing aid accessibility, affordability, and use;
2. The appropriateness of creating a category of “basic” hearing aids with labeling for OTC sale; and
3. Whether the benefits of OTC hearing aids would outweigh the risks of foregoing the requirement of medical evaluation.

Concurrently with reopening the comment period on the PSAP draft guidance, FDA also announced a public workshop (held in April 2016) to discuss the current quality system and good manufacturing practices requirements that apply to hearing aids (FDA, 2016b). FDA indicated that it would consider proposals for an alternative model for quality verification and quality standards developed by standards development organizations and key stakeholders.

FDA Regulatory Policy for Mobile Apps and General Wellness Products

The proliferation of mobile apps and consumer-oriented products intended for health and medical uses has challenged FDA with regard to where to draw the line between devices and nondevices. Some of the mobile apps under development might be useful in providing hearing assistance or enabling hearing assistive technologies (see Chapter 3). Some mobile apps might be represented as PSAPs. FDA has issued two guidance documents, one on mobile apps and the other on general wellness products (FDA, 2015a,b). As with PSAPs, FDA has tried to distinguish “medical device” products and uses from nondevice products. FDA has also described generic types of products that might be medical devices but that FDA would not affirmatively regulate in its exercise of enforcement discretion.

FDA has long held the view that software can be a medical device when it meets the statutory definition of “device.” This includes software that controls a medical device, software that is an accessory to a device, and freestanding software that performs a device function. FDA’s guidance document on mobile medical apps states that a mobile app meets the definition of device when it is intended either to be used as an accessory to a regulated medical device or to transform a mobile platform into a regulated medical device (FDA, 2015b). For example, the guidance states that a mobile app that functions as a stethoscope would be a mobile medical app subject to device regulation. By analogy, a mobile app that functions as a hearing aid would be a device.

Also relevant to hearing health, FDA’s guidance document states that apps intended for use as audiometers are mobile medical apps:

On the other hand, mobile apps that provide a checklist of symptoms to advise a consumer on when to see a physician, general educational tools, or tools that help a consumer communicate with a health care professional would not be medical apps.

To increase the availability to consumers of health-related technologies, FDA’s draft guidance document on general wellness products describes categories of low-risk products that would not be subject to regulation as medical devices (FDA, 2015a). A general wellness product is described as having “(1) an intended use that relates to maintaining or encouraging a general state of health or healthy activity or (2) an intended use claim that associates the role of healthy lifestyle with helping to reduce the risk or impact of certain chronic diseases or conditions” (FDA, 2015a, p. 3). The former category includes products for weight management, improving mental acuity, and other such claimed effects where there is no reference to a disease, disorder, or medical condition. An intervention or technology that may pose a risk to user safety (such as radiation exposure) or that raises novel questions of usability is not considered to be low risk.

Both the mobile apps guidance and the general wellness guidance indicate that rapid advances in health-related technologies are driving consumer demand and that industry is responding by developing a broad array of products. FDA, in turn, has sought to respond to these products with a risk-based approach to the enforcement of its medical device regulations.

The committee provides details later in this chapter on its recommendation to FDA to establish a new category of OTC wearable hearing devices.

State Laws Relating to Hearing Aids and Hearing Aid Dispensing

Types of State Laws Affecting Hearing Aids and Dispensing

Numerous states have enacted laws that affect sales of “hearing aids” as defined in the state law. These state laws typically define a “hearing aid” as a wearable instrument or device intended for the purpose of “aiding

or compensating for impaired human hearing,” for improving the hearing of a “hearing-impaired person,” or “aiding or improving defective human hearing.”²⁹

State laws require the licensing of persons who sell, rent, lease, dispense, or otherwise provide a hearing aid to a consumer. Some state laws require an evaluation or measurement of hearing prior to selling a hearing aid. Some state laws prohibit the sale or distribution of hearing aids through the mail or via the Internet, while other state laws permit such sale or distribution under specified conditions.

States also typically have unfair trade practice laws and consumer protection laws that apply to the promotion and sales of products, which could include hearing aids as well as PSAPs. Other state laws of general applicability might also be relevant, but they are beyond the scope of this review.

Relationship Between FDA and State Regulatory Requirements

There is a complicated relationship between FDA regulations and state laws as they apply to medical devices, and this relationship is particularly relevant to the regulation of hearing aids. Section 521(a) of the FDCA contains an “express preemption” provision applicable to medical devices. Under that provision, no state or local government

In essence, an FDA requirement applicable to a device that relates to either the safety and effectiveness of the device or a specific requirement for the device established under the FDCA preempts any state or local requirement that is not consistent with the FDA requirement.

State or local requirements are preempted only when FDA has established specific regulations or there are other specific requirements applicable to a particular device under the FDCA. Under FDA’s regulations, some state or local requirements affect devices but are not preempted by section 521(a) because they are not “requirements applicable to a device.” These include laws of general applicability to device and nondevice products (e.g., unfair

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²⁹ E.g., California Business and Professions Code § 2538.10(d); Florida Statutes Chapter 484.041(5); Georgia Code Annotated § 43-20-3(5); Michigan Compiled Laws § 339.1301(a).

trade practices) and licensing laws that relate to the practice of medicine or related professions or occupations that administer, dispense, or sell devices.

“Restricted device” regulations issued under section 520(e) may impose restrictions on the sale, distribution, or use of a device beyond those prescribed in state or local requirements. If there is a conflict between such restrictions and state or local requirements, FDA’s federal regulations prevail. This would include the restrictions imposed on hearing aid labeling and sales.

Section 521(b) of the FDCA contains a provision whereby FDA may allow the imposition of a state requirement that is different from, or in addition to, any requirement applicable under the act to the device (and which is thereby preempted) by promulgating an FDA regulation exempting the state or local requirement from preemption. FDA’s regulations in 21 C.F.R. Part 808 list numerous state requirements that FDA has exempted from preemption, and many of these apply to state requirements applicable to hearing aids and the dispensing of hearing aids.

FDA has treated state licensing laws and terms-of-sale laws as state requirements that are not expressly preempted by section 521(a). In contrast, FDA considers that state disclosure and recordkeeping laws, state laws requiring an audiological evaluation before the sale of a hearing aid to a minor, and state laws that are substantially identical to federal requirements would be preempted by section 521(a). Nevertheless, FDA has decided affirmatively to exempt these laws from federal preemption through the rule-making exemption procedure.³⁰

A manufacturer seeking to market an OTC hearing aid or other innovative hearing assistive technology product thus faces at least four principal hurdles:

1. Federal regulations impose “restricted use” requirements on hearing aid dispensers regarding warnings and information that they must disclose to and obtain from consumers prior to a sale, as well as other conditions on the sale of hearing aids;³¹
2. Federal regulations exempt from federal preemption any state laws that (i) require hearing aid dispensers to disclose certain additional information related to the safety and efficacy of hearing aids or that provide consumers with advice at the time of sale, or both; and (ii) impose additional recordkeeping requirements on dispensers;³²

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³⁰ See 21 C.F.R. § 808.20 et seq. (describing the exemption procedure); 21 C.F.R. § 808.53 et seq. (listing the exemptions applicable to all states and identifying the specific hearing aid laws of 19 states and the District of Columbia that have been exempted from preemption).

³¹ FDCA § 520(e); 21 C.F.R. §§ 801.420-801.421.

³² 21 C.F.R. Part 808; 45 Fed. Reg. 67326 (1980).

3. Federal regulations exempt from federal preemption state requirements that are “equal to, or substantially identical to, requirements imposed by or under” the FDCA;³³ and
4. FDA has by regulation and in statements in the Federal Register interpreted the FDCA as not expressly preempting (i) state laws related to the licensing, registration, and certification of hearing aid dispensers; and (ii) state regulations that require hearing aid dispensers to disclose at the time of sale certain information related to the terms of sale (does not include information related to the safety or effectiveness of hearing aids).³⁴

In sum, under FDA’s current regulations relating to preemption and exemptions from preemption for state laws relating to hearing aids and dispensing, manufacturers would need to consider various state laws and determine whether innovative technologies and marketing approaches would contravene either federal or state regulatory requirements. These state law requirements impose barriers to improving the accessibility and affordability of hearing aids and hearing technologies, in addition to any FDA-related barriers.

Federal Trade Commission

The FTC enforces laws that prohibit fraudulent, unfair, and deceptive trade practices.³⁵ FTC regulations prohibit the use of misleading sales and advertising practices, including giving inaccurate information about hearing loss, hearing aid performance, refund policies, or warranty coverage.

The FTC website advises consumers that the purchase agreement for a hearing aid should include information regarding the trial period for the product, the warranty, the total price, and what is available during service or repair (e.g., a loaner hearing aid) (FTC, 2016). The FTC also advises consumers about the FDA requirements applicable to hearing aids.

The FTC also provides advice relating to PSAPs. For example, the FTC website states: “Sound Advice: If your hearing is impaired, don’t use a PSAP as a substitute for a hearing aid. That may delay the diagnosis of a potentially treatable condition, and cause more damage to your hearing” (FTC, 2016).

Thus, FDA, FTC, and states could bring enforcement with respect to misleading promotional practices for hearing aids and PSAPs.

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³³ 21 C.F.R. § 808.1(d)(2).

³⁴ 21 C.F.R. § 808.1(d)(3); 42 Fed. Reg. 9285, 9293 (1977); 45 Fed. Reg. 67326, 67331(1980).

³⁵ Federal Trade Commission Act, 15 U.S.C. §§ 41-58 as amended.

Federal Communications Commission

The FCC is responsible for enforcing several laws intended to enable Americans with hearing loss to have greater access to wire-line and wireless communications services and emerging communications technologies. These laws include the Hearing Aid Compatibility Act of 1988³⁶ and the Twenty-First Century Communications and Video Accessibility Act of 2010 (CVAA),³⁷ which expanded accessibility laws to newer technologies, including digital, broadband, and mobile innovations (see Box 4-4).

The Hearing Aid Compatibility Act required the FCC to ensure that all wire-line telephones manufactured or imported for use in the United States and all “essential” telephones such as public phones, hospital and nursing home phones, emergency phones, and workplace phones are hearing aid compatible.³⁸ Cell phones (which were not common in 1988) were exempted, but the statute authorized the FCC to limit or eliminate that exemption.

In 2003, with the widespread availability of wireless phones, the FCC required manufacturers of wireless phones to make available a certain number or percentage of models that are hearing aid compatible.³⁹ The FCC established rules for hearing aid compatibility of digital wireless phones and to wire-line and wireless communications services through a wide array of phones, including voice-over-Internet protocol telephones and wireless handsets that use advanced mobile technologies.

FCC rules require that phones subject to the Hearing Aid Compatibility Act produce a magnetic field of sufficient strength and quality to permit coupling with hearing aids that contain telecoils. The telecoil picks up the voice signal from an electromagnetic signal from the telephone, enabling users of telecoil-equipped hearing aids to communicate over the telephone without feedback and without the amplification of unwanted background noise. FCC rules also establish technical parameters to ensure that telephones are compatible with hearing aids.⁴⁰

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³⁶ Hearing Aid Compatibility Act of 1988, Public Law 100-394, 100th Cong. (August 16, 1988). 47 U.S.C. § 610.

³⁷ Twenty-First Century Communications and Video Accessibility Act of 2010, Public Law 111-260, 111th Cong., 2d sess. (October 8, 2010) and amendments, 124 Stat. 2795 (2010) (as codified in various sections of 47 U.S.C.).

³⁸ 47 U.S.C. § 610(b).

³⁹ The FCC issued a Notice of Proposed Rulemaking in November 2015 to require that all wireless handsets, not just a certain percentage of models, be hearing aid compatible in accordance with a staged plan for implementation. Fourth Report and Order, and Notice of Proposed Rulemaking, FCC 15-155 (November 19, 2015).

⁴⁰ ANSI standard C63.19 sets forth the standard for compatibility of digital wireless phones with hearing aids. A digital wireless handset is considered hearing aid compatible for inductive coupling if it meets a T3 (or U3T) rating under the ANSI standard. The ANSI standard also provides a methodology for rating hearing aids from M1 to M4, with M1 being the least immune to radio-frequency interference (including stray signals from the wireless phone) and M4 being the most immune.

FCC rules also generally require that telephones allow the volume to be increased to accommodate individuals with hearing loss, whether or not they use hearing aids. Telephones allowing high volume levels must automatically reset to a lower volume each time the handset is returned to an on-hook condition (unless a waiver is granted in certain conditions).

Telephone manufacturers and wireless service providers are required to provide certain types of information to consumers in their product labeling and packaging for hearing aid–compatible products, and on their websites. Manufacturers and wireless carriers must also file annual reports with the FCC that list their hearing aid–compatible products.

Enacted in 2010, the CVAA updates the FCC requirements to address modern communications. Title I of the statute addresses telecommunications access issues to make advanced communications products and services fully accessible to people with disabilities. These services include voice-over-Internet protocol services and electronic messaging. For example, smartphones are required to be usable by people with hearing aids as well as by individuals who are blind or have vision impairments. Title II addresses video programming to make it easier for people with disabilities to view video programming on television and the Internet. For example, programs shown on television with captioning are required to include the captioning when they are distributed on the Internet. The statute also requires that people with disabilities have access to emergency information, including next-generation 911 services and emergency information on the television.

The FCC recently proposed to amend the hearing aid compatibility rules for wire-line handsets. The proposal would incorporate revised industry standards relating to volume control and set a standard for volume control for wireless handsets intended to ensure more effective acoustic coupling between handsets and hearing aids or cochlear implants.⁴¹

In November 2015, the FCC adopted new rules to expand hearing aid compatibility requirements to technologies such as Wi-Fi calling and Voice over Long-Term Evolution.⁴² To avoid regulatory requirements lagging behind technological advances, these new rules also require that future technologies automatically comply with hearing aid compatibility rules.

One question that arises is whether the FCC regulations would govern compatibility with PSAPs, which are not considered “hearing aid” devices as defined by FDA. The answer to this question might depend on which rules are at issue. The FCC accessibility rules require noninterference with hearing technologies—defined to include hearing aids, cochlear implants, and hearing assistive technologies—to the lowest possible level that allows

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⁴¹ Notice of Proposed Rulemaking, FCC 15-144, adopted October 23, 2015.

⁴² Fourth Report and Order, and Notice of Proposed Rulemaking, FCC 15-155, adopted November 19, 2015.

a user to utilize the product.⁴³ In contrast, hearing aid coupling is defined as applicable to “effective wireless coupling to hearing aids.”⁴⁴ The hearing aid compatibility rules assume that the ANSI standard applicable to hearing aids would apply in addition to the ANSI standard for handsets to achieve compatibility, which would appear to exclude the possibility of PSAPs not complying with that standard.⁴⁵

Americans with Disabilities Act

The ADA includes requirements for nationwide telecommunications relay services and telephone access to local emergency services (911 call centers). Section 508 of the Rehabilitation Act of 1973 included provisions relating to accessibility to telecommunications technologies that are acquired and provided by the federal government.

Litigation under the ADA has been used to try to expand accessibility to communications technology. For example, there are court decisions with inconsistent outcomes as to whether a website for an entity that does not have a physical location open to the public is subject to ADA requirements relating to public accommodations.⁴⁶ The Department of Justice has not issued regulations regarding applicability to websites, but it has suggested that the ADA would obligate public accommodations to make the websites that they use to provide their goods and services accessible to and usable by individuals with disabilities.⁴⁷

These statutes, enforced by private litigants as well as the Department of Justice, might also encourage the development of advanced communications technologies that are accessible and usable by individuals with hearing loss.

Voluntary Standards

Voluntary standards are being developed for PSAPs through the CTA. CTA is accredited through ANSI to develop standards and other technical documents for the consumer electronics industry. CTA voluntary standards committees engage industry, academia, consumers, and other constituencies in the development of performance criteria, measurement protocols, and other specifications. In 2015, CTA committee R6WG20 was finalizing a set of minimum performance metrics for PSAPs and a glossary of PSAP-related terms (Belt, 2015). Discussions are under way regarding the potential for

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⁴³ 47 C.F.R. § 6.3(a)(2)(viii).

⁴⁴ 47 C.F.R. § 6.3(a)(2)(ix).

⁴⁵ 47 C.F.R. § 20.19(b).

⁴⁶ See discussion in the federal district court’s opinion in National Federation of the Blind v. Scribd Inc., Case No. 2:14-cv-162 (D. Vt., March 19, 2015).

⁴⁷ 80 Fed. Reg. 35044 (June 18, 2015).

a logo program or other mechanism to identify products that meet the performance standards to aid consumers in comparing PSAPs (Belt, 2015).

As noted above, FDA has recognized consensus standards that are applicable to hearing aids, including ANSI/ASA standards. These standards are intended to ensure the quality and performance of these devices. The standards address issues such as specifications of hearing aid characteristics, signal processing, the computation of loudness and speech intelligibility, measuring the intelligibility of speech over communications systems, and measuring performance characteristics under simulated real-world working conditions.

NEXT STEPS AND RECOMMENDATIONS

The broad spectrum of types and severity of hearing loss necessitates a wide range of hearing technologies to meet each individual’s needs with options that adhere to safety requirements and are effective in improving hearing and communication in the complex environments of daily life. Interoperability with other technologies including cell phones, televisions, and emergency alert systems is critical.

Develop and Clarify Hearing Device Options

FDA’s hearing aid regulations along with state laws relating to hearing aid sales and dispensing place obstacles in the way of new technologies that could make hearing assistance more easily available and accessible for adults who could benefit from such assistance in connection with mild to moderate hearing loss. As noted throughout this report, innovation in technologies relevant to hearing loss are occurring that can provide affordable, effective, safe, and usable technologies to address the unmet need for hearing health care. The committee carefully examined the regulatory and policy challenges and opportunities for expanding innovative technologies and thus provides a range of options for individuals with hearing loss.

FDA sought to carve out PSAPs as a category of nondevice products that could be more easily marketed. But FDA has defined PSAPs as being intended only for a user population of persons without hearing loss, while hearing aids are intended to compensate for hearing loss. Thus, PSAP manufacturers and distributors are not supposed to be offering their products for the purpose of compensating for hearing loss. This legal and regulatory distinction between hearing aids and PSAPs might not be readily apparent to users, and it might not be fully respected by PSAP sellers who explicitly or implicitly offer their products to compensate for hearing loss.

By taking this approach of removing PSAPs from device regulation, FDA has left PSAPs largely unregulated, without the design control requirements, performance standards, technical standards, or labeling

requirements that apply to devices. The FTC would still apply its regulations prohibiting fraudulent, unfair, and deceptive trade practices, but that is a post-market enforcement that might put consumers at risk.

An approach that could better protect consumers and offer options for more informed consumer decision making would be for FDA to create a category of “OTC wearable hearing devices” intended for mild to moderate hearing loss. In order to ensure their safety and effectiveness, these devices could be subject to ANSI and other technical standards applicable to hearing aid performance. They would be exempted from premarket review if the technology was fundamentally the same as Class I air-conduction hearing aids, or else they would be subject to 510(k) notification if the technology was similar to the Class II hearing aid devices. These OTC wearable hearing devices would be subject to labeling requirements tailored to OTC selection, purchase, and use.

This regulatory approach would be similar to the FDA’s regulatory approach of creating separate device classification regulations for “prescription eyeglasses” and “magnifying spectacles.”⁴⁸ Magnifying spectacles are “convex lenses intended to be worn by a patient who has impaired vision to enlarge images.” In contrast, prescription spectacle lenses “provide refractive corrections in accordance with a prescription for the patient.” Similarly, a category of OTC wearable hearing devices could provide a simpler technological approach to improving hearing (e.g., amplification) than would a more complicated technology. (The parallel drawn with eyeglass regulation is specific to the regulatory approach and is not meant to draw parallels between the use and performance of the devices.) FDA has moved a variety of monitoring and therapeutic technologies to OTC status (such as noninvasive blood pressure monitoring systems, stethoscopes, burn dressings, medications) to enable consumers and patients to take more control of their own health and medical conditions.

In implementing an OTC wearable hearing device category, FDA should preempt state laws that could pose an obstacle to implementation. For example, FDA should preempt any state laws or regulations that would purport to prohibit OTC sale and distribution of these hearing devices, or purport to require dispensing, fitting, or evaluation by a licensed audiologist, hearing instrument specialist, or other professional occupation prior to purchase of these OTC wearable hearing devices. Various approaches to preemption could be considered by FDA. For example, preemption might be accomplished by making the OTC wearable hearing devices a new category of “restricted devices” (apart from the current regulations in 21 C.F.R. §§ 801.420 and 801.421) such that the FDA regulations would be requirements specifically applicable to the safety and

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⁴⁸ 21 C.F.R. §§ 886.5840, 886.5844.

effectiveness of this category of OTC wearable hearing device. In addition, the “OTC wearable hearing devices” would not be called “hearing aids,” with the intention of avoiding application of state laws that already refer to and govern “hearing aids.”

An alternative option that the committee considered was to retain the category of PSAP as a nondevice product that would be permitted to include claims to compensate for “normal” hearing loss as a result of aging. In essence, age-related hearing loss would not be considered a “disease,” and thus the products would not be considered as within the statutory definition of “device.” To keep PSAPs outside the device definition, FDA would also have to conclude that PSAPs are not intended to affect a structure or function of the body. This approach would not preempt state laws, however, and many state laws define “hearing aids” as instruments compensating for hearing loss and subject them to dispensing requirements. If the PSAPs claim to compensate for hearing loss, they might be swept into these state laws. Furthermore, this approach would not establish a framework for regulating the quality of PSAPs, the performance claims made for them, or the adequacy of labeling information provided to users—all of which are important considerations.

As medical devices, the OTC wearable hearing devices would be subject to regulatory requirements such as establishment registration (including payment of an annual user fee by the manufacturer), device listing, good manufacturing practices, labeling, and reporting. Compliance with FDA requirements would add to the costs of manufacturing and distribution of these devices. Nonetheless, compliance with these requirements would also provide safety and effectiveness benefits for users. FDA could apply the types of consensus standards that would be applicable to the performance of the OTC wearable hearing devices and also tailor or exempt certain regulatory requirements, such as specific quality system regulations, good manufacturing practices, or reporting requirements, as appropriate to the OTC wearable hearing devices.

Consumer-focused information (e.g., consumer education programs, user instructional brochures, package inserts, as well as specific labeling) will be important for OTC wearable hearing devices. Some OTC devices could be accompanied by software or apps for self-fitting and adjustment of the devices. The sales of OTC wearable hearing devices are anticipated to be similar to other OTC product sales with many reputable products having warranties and return policies. FTC requirements would continue to apply to protect consumers from fraudulent practices. The committee’s recommendations regarding the OTC wearable hearing device category are generally consistent with the PCAST recommendation regarding the need for OTC devices (PCAST, 2015) but differ in certain respects and are more specific.

The committee recognizes the need for an FDA guidance document regarding PSAPs to clarify that PSAPs are for specific purposes not related to hearing loss in contrast to hearing aids and OTC wearable hearing devices that are aimed at addressing hearing loss. The committee believes that this guidance could be accomplished by retaining the 2009 PSAP guidance or through revisions to the 2013 document including recognition that PSAPs are for specific hearing situations not related to hearing loss. As noted above, this distinction would be important to maintain in order to ensure that consumers with hearing loss receive the benefits relating to quality, performance, compatibility, and labeling envisioned under the OTC wearable hearing device category.

The committee notes that these changes would result in a wider range of options for adults with hearing loss, particularly mild to moderate hearing loss (see Table 4-2) and would clarify the purpose of PSAPs (see Table 4-3).

TABLE 4-2
Proposed Range of Hearing-Related Devices and Products for Individuals with Hearing Loss

NOTE: ANSI = American National Standards Institute; CPSC = Consumer Product Safety Commission; FCC = Federal Communications Commission; FDA = Food and Drug Administration; FTC = Federal Trade Commission; OTC = over the counter.

TABLE 4-3
Consumer Products for Amplifying Sound

NOTE: CPSC = Consumer Product Safety Commission; CTA = Consumer Technology Association; FDA = Food and Drug Administration; FDCA = Federal Food, Drug, and Cosmetic Act; FTC = Federal Trade Commission; OTC = over the counter; PSAP = personal sound amplification product.

Improve Transparency, Compatibility, and Interoperability of Hearing Technologies and Telecommunications Systems

Individuals with hearing loss frequently use hearing aids with telecoils or other hearing assistive technologies to couple with many other electronic communications products. These individuals benefit from compatibility between and among products and from interoperable systems such as emergency communication system connections, text-to-911, and captioning of alerts. Performance standards and policies can ensure the needed interoperability among products so that the products can easily and seamlessly connect and provide optimum sound transmission and performance (see also Chapter 6). For example, the standards relevant to hearing aid telecoils and hearing induction loop technology ensure that consumers can use the telecoil available across many brands of hearing aids to effectively connect to induction loop systems from a number of different manufacturers that are available in a variety of public spaces.⁴⁹ Similar efforts are needed to standardize the interfaces and connection points of hearing aids, hearing assistive technologies, and OTC wearable hearing devices with other types of technologies and communications systems.

As discussed earlier in the chapter, an open platform for programming hearing aid settings could also increase accessibility to the devices and related services. The committee encourages standards development related to open platforms. An open platform approach would provide consumers with greater portability in their hearing health care including increasing the options for choosing their hearing health care professional. Consumers should

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⁴⁹ The interoperability between telecoils in hearing aids and hearing induction loop technology is possible due to national and international standards that can be used by both technologies (e.g., International Electrotechnical Commission’s standard, IEC 60118-4 [IEC, 2014]). It is the committee’s understanding that efforts are under way to examine referencing the recently updated hearing induction loop standards in the International Building Code and the International Code Council/American National Standards Institute standard A117.1 regarding accessible buildings (Kirkwood, 2013).

be notified prior to sale regarding the portability of hearing aid programming. Greater public awareness and user-friendly instructions about the availability, portability, connectivity, and use of hearing aids and hearing assistive technologies, as well as comparable details on product features, are needed to enable informed decision making.

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